src/gbm/main/gbm.c

   1 /*
   2  * Copyright © 2011 Intel Corporation
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice (including the next
  12  * paragraph) shall be included in all copies or substantial portions of the
  13  * Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  16  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  17  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  18  * NONINFRINGEMENT.  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
  19  * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
  20  * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  22  * DEALINGS IN THE SOFTWARE.
  23  *
  24  * Authors:
  25  *    Benjamin Franzke <benjaminfranzke@googlemail.com>
  26  */
  27
  28 #include <stddef.h>
  29 #include <stdio.h>
  30 #include <stdlib.h>
  31 #include <string.h>
  32 #include <stdint.h>
  33
  34 #ifdef MAJOR_IN_MKDEV
  35 #include <sys/mkdev.h>
  36 #endif
  37 #ifdef MAJOR_IN_SYSMACROS
  38 #include <sys/sysmacros.h>
  39 #endif
  40 #include <sys/stat.h>
  41 #include <unistd.h>
  42 #include <errno.h>
  43
  44 #include "gbm.h"
  45 #include "gbmint.h"
  46 #include "backend.h"
  47
  48 /** Returns the file description for the gbm device
  49  *
  50  * \return The fd that the struct gbm_device was created with
  51  */
  52 GBM_EXPORT int
  53 gbm_device_get_fd(struct gbm_device *gbm)
  54 {
  55    return gbm->fd;
  56 }
  57
  58 /* FIXME: maybe superfluous, use udev subclass from the fd? */
  59 /** Get the backend name for the given gbm device
  60  *
  61  * \return The backend name string - this belongs to the device and must not
  62  * be freed
  63  */
  64 GBM_EXPORT const char *
  65 gbm_device_get_backend_name(struct gbm_device *gbm)
  66 {
  67    return gbm->name;
  68 }
  69
  70 /** Test if a format is supported for a given set of usage flags.
  71  *
  72  * \param gbm The created buffer manager
  73  * \param format The format to test
  74  * \param usage A bitmask of the usages to test the format against
  75  * \return 1 if the format is supported otherwise 0
  76  *
  77  * \sa enum gbm_bo_flags for the list of flags that the format can be
  78  * tested against
  79  *
  80  * \sa enum gbm_bo_format for the list of formats
  81  */
  82 GBM_EXPORT int
  83 gbm_device_is_format_supported(struct gbm_device *gbm,
  84                                uint32_t format, uint32_t usage)
  85 {
  86    return gbm->is_format_supported(gbm, format, usage);
  87 }
  88
  89 /** Destroy the gbm device and free all resources associated with it.
  90  *
  91  * \param gbm The device created using gbm_create_device()
  92  */
  93 GBM_EXPORT void
  94 gbm_device_destroy(struct gbm_device *gbm)
  95 {
  96    gbm->refcount--;
  97    if (gbm->refcount == 0)
  98       gbm->destroy(gbm);
  99 }
 100
 101 /** Create a gbm device for allocating buffers
 102  *
 103  * The file descriptor passed in is used by the backend to communicate with
 104  * platform for allocating the memory. For allocations using DRI this would be
 105  * the file descriptor returned when opening a device such as \c
 106  * /dev/dri/card0
 107  *
 108  * \param fd The file descriptor for a backend specific device
 109  * \return The newly created struct gbm_device. The resources associated with
 110  * the device should be freed with gbm_device_destroy() when it is no longer
 111  * needed. If the creation of the device failed NULL will be returned.
 112  */
 113 GBM_EXPORT struct gbm_device *
 114 gbm_create_device(int fd)
 115 {
 116    struct gbm_device *gbm = NULL;
 117    struct stat buf;
 118
 119    if (fd < 0 || fstat(fd, &buf) < 0 || !S_ISCHR(buf.st_mode)) {
 120       errno = EINVAL;
 121       return NULL;
 122    }
 123
 124    gbm = _gbm_create_device(fd);
 125    if (gbm == NULL)
 126       return NULL;
 127
 128    gbm->dummy = gbm_create_device;
 129    gbm->stat = buf;
 130    gbm->refcount = 1;
 131
 132    return gbm;
 133 }
 134
 135 /** Get the width of the buffer object
 136  *
 137  * \param bo The buffer object
 138  * \return The width of the allocated buffer object
 139  *
 140  */
 141 GBM_EXPORT unsigned int
 142 gbm_bo_get_width(struct gbm_bo *bo)
 143 {
 144    return bo->width;
 145 }
 146
 147 /** Get the height of the buffer object
 148  *
 149  * \param bo The buffer object
 150  * \return The height of the allocated buffer object
 151  */
 152 GBM_EXPORT unsigned int
 153 gbm_bo_get_height(struct gbm_bo *bo)
 154 {
 155    return bo->height;
 156 }
 157
 158 /** Get the stride of the buffer object
 159  *
 160  * This is calculated by the backend when it does the allocation in
 161  * gbm_bo_create()
 162  *
 163  * \param bo The buffer object
 164  * \return The stride of the allocated buffer object in bytes
 165  */
 166 GBM_EXPORT uint32_t
 167 gbm_bo_get_stride(struct gbm_bo *bo)
 168 {
 169    return bo->stride;
 170 }
 171
 172 /** Get the format of the buffer object
 173  *
 174  * The format of the pixels in the buffer.
 175  *
 176  * \param bo The buffer object
 177  * \return The format of buffer object, on of the GBM_FORMAT_* codes
 178  */
 179 GBM_EXPORT uint32_t
 180 gbm_bo_get_format(struct gbm_bo *bo)
 181 {
 182    return bo->format;
 183 }
 184
 185 /** Get the handle of the buffer object
 186  *
 187  * This is stored in the platform generic union gbm_bo_handle type. However
 188  * the format of this handle is platform specific.
 189  *
 190  * \param bo The buffer object
 191  * \return Returns the handle of the allocated buffer object
 192  */
 193 GBM_EXPORT union gbm_bo_handle
 194 gbm_bo_get_handle(struct gbm_bo *bo)
 195 {
 196    return bo->handle;
 197 }
 198
 199 /** Get a DMA-BUF file descriptor for the buffer object
 200  *
 201  * This function creates a DMA-BUF (also known as PRIME) file descriptor
 202  * handle for the buffer object.  Each call to gbm_bo_get_fd() returns a new
 203  * file descriptor and the caller is responsible for closing the file
 204  * descriptor.
 205
 206  * \param bo The buffer object
 207  * \return Returns a file descriptor referring to the underlying buffer or -1
 208  * if an error occurs.
 209  */
 210 GBM_EXPORT int
 211 gbm_bo_get_fd(struct gbm_bo *bo)
 212 {
 213    return bo->gbm->bo_get_fd(bo);
 214 }
 215
 216
 217 /** Write data into the buffer object
 218  *
 219  * If the buffer object was created with the GBM_BO_USE_WRITE flag,
 220  * this function can be used to write data into the buffer object.  The
 221  * data is copied directly into the object and it's the responsibility
 222  * of the caller to make sure the data represents valid pixel data,
 223  * according to the width, height, stride and format of the buffer object.
 224  *
 225  * \param bo The buffer object
 226  * \param buf The data to write
 227  * \param count The number of bytes to write
 228  * \return Returns 0 on success, otherwise -1 is returned an errno set
 229  */
 230 GBM_EXPORT int
 231 gbm_bo_write(struct gbm_bo *bo, const void *buf, size_t count)
 232 {
 233    return bo->gbm->bo_write(bo, buf, count);
 234 }
 235
 236 /** Get the gbm device used to create the buffer object
 237  *
 238  * \param bo The buffer object
 239  * \return Returns the gbm device with which the buffer object was created
 240  */
 241 GBM_EXPORT struct gbm_device *
 242 gbm_bo_get_device(struct gbm_bo *bo)
 243 {
 244         return bo->gbm;
 245 }
 246
 247 /** Set the user data associated with a buffer object
 248  *
 249  * \param bo The buffer object
 250  * \param data The data to associate to the buffer object
 251  * \param destroy_user_data A callback (which may be %NULL) that will be
 252  * called prior to the buffer destruction
 253  */
 254 GBM_EXPORT void
 255 gbm_bo_set_user_data(struct gbm_bo *bo, void *data,
 256                      void (*destroy_user_data)(struct gbm_bo *, void *))
 257 {
 258    bo->user_data = data;
 259    bo->destroy_user_data = destroy_user_data;
 260 }
 261
 262 /** Get the user data associated with a buffer object
 263  *
 264  * \param bo The buffer object
 265  * \return Returns the user data associated with the buffer object or %NULL
 266  * if no data was associated with it
 267  *
 268  * \sa gbm_bo_set_user_data()
 269  */
 270 GBM_EXPORT void *
 271 gbm_bo_get_user_data(struct gbm_bo *bo)
 272 {
 273    return bo->user_data;
 274 }
 275
 276 /**
 277  * Destroys the given buffer object and frees all resources associated with
 278  * it.
 279  *
 280  * \param bo The buffer object
 281  */
 282 GBM_EXPORT void
 283 gbm_bo_destroy(struct gbm_bo *bo)
 284 {
 285    if (bo->destroy_user_data)
 286       bo->destroy_user_data(bo, bo->user_data);
 287
 288    bo->gbm->bo_destroy(bo);
 289 }
 290
 291 /**
 292  * Allocate a buffer object for the given dimensions
 293  *
 294  * \param gbm The gbm device returned from gbm_create_device()
 295  * \param width The width for the buffer
 296  * \param height The height for the buffer
 297  * \param format The format to use for the buffer
 298  * \param usage The union of the usage flags for this buffer
 299  *
 300  * \return A newly allocated buffer that should be freed with gbm_bo_destroy()
 301  * when no longer needed. If an error occurs during allocation %NULL will be
 302  * returned and errno set.
 303  *
 304  * \sa enum gbm_bo_format for the list of formats
 305  * \sa enum gbm_bo_flags for the list of usage flags
 306  */
 307 GBM_EXPORT struct gbm_bo *
 308 gbm_bo_create(struct gbm_device *gbm,
 309               uint32_t width, uint32_t height,
 310               uint32_t format, uint32_t usage)
 311 {
 312    if (width == 0 || height == 0) {
 313       errno = EINVAL;
 314       return NULL;
 315    }
 316
 317    return gbm->bo_create(gbm, width, height, format, usage);
 318 }
 319
 320 /**
 321  * Create a gbm buffer object from an foreign object
 322  *
 323  * This function imports a foreign object and creates a new gbm bo for it.
 324  * This enabled using the foreign object with a display API such as KMS.
 325  * Currently three types of foreign objects are supported, indicated by the type
 326  * argument:
 327  *
 328  *   GBM_BO_IMPORT_WL_BUFFER
 329  *   GBM_BO_IMPORT_EGL_IMAGE
 330  *   GBM_BO_IMPORT_FD
 331  *
 332  * The gbm bo shares the underlying pixels but its life-time is
 333  * independent of the foreign object.
 334  *
 335  * \param gbm The gbm device returned from gbm_create_device()
 336  * \param gbm The type of object we're importing
 337  * \param gbm Pointer to the external object
 338  * \param usage The union of the usage flags for this buffer
 339  *
 340  * \return A newly allocated buffer object that should be freed with
 341  * gbm_bo_destroy() when no longer needed. On error, %NULL is returned
 342  * and errno is set.
 343  *
 344  * \sa enum gbm_bo_flags for the list of usage flags
 345  */
 346 GBM_EXPORT struct gbm_bo *
 347 gbm_bo_import(struct gbm_device *gbm,
 348               uint32_t type, void *buffer, uint32_t usage)
 349 {
 350    return gbm->bo_import(gbm, type, buffer, usage);
 351 }
 352
 353 /**
 354  * Map a region of a gbm buffer object for cpu access
 355  *
 356  * This function maps a region of a gbm bo for cpu read and/or write
 357  * access.
 358  *
 359  * \param bo The buffer object
 360  * \param x The X (top left origin) starting position of the mapped region for
 361  * the buffer
 362  * \param y The Y (top left origin) starting position of the mapped region for
 363  * the buffer
 364  * \param width The width of the mapped region for the buffer
 365  * \param height The height of the mapped region for the buffer
 366  * \param flags The union of the GBM_BO_TRANSFER_* flags for this buffer
 367  * \param stride Ptr for returned stride in bytes of the mapped region
 368  * \param map_data Returned opaque ptr for the mapped region
 369  *
 370  * \return Address of the mapped buffer that should be unmapped with
 371  * gbm_bo_unmap() when no longer needed. On error, %NULL is returned
 372  * and errno is set.
 373  *
 374  * \sa enum gbm_bo_transfer_flags for the list of flags
 375  */
 376 GBM_EXPORT void *
 377 gbm_bo_map(struct gbm_bo *bo,
 378               uint32_t x, uint32_t y,
 379               uint32_t width, uint32_t height,
 380               uint32_t flags, uint32_t *stride, void **map_data)
 381 {
 382    if (!bo || width == 0 || height == 0 || !stride || !map_data) {
 383       errno = EINVAL;
 384       return NULL;
 385    }
 386
 387    return bo->gbm->bo_map(bo, x, y, width, height,
 388                           flags, stride, map_data);
 389 }
 390
 391 /**
 392  * Unmap a previously mapped region of a gbm buffer object
 393  *
 394  * This function unmaps a region of a gbm bo for cpu read and/or write
 395  * access.
 396  *
 397  * \param bo The buffer object
 398  * \param map_data opaque ptr returned from prior gbm_bo_map
 399  */
 400 GBM_EXPORT void
 401 gbm_bo_unmap(struct gbm_bo *bo, void *map_data)
 402 {
 403    bo->gbm->bo_unmap(bo, map_data);
 404 }
 405
 406 /**
 407  * Allocate a surface object
 408  *
 409  * \param gbm The gbm device returned from gbm_create_device()
 410  * \param width The width for the surface
 411  * \param height The height for the surface
 412  * \param format The format to use for the surface
 413  *
 414  * \return A newly allocated surface that should be freed with
 415  * gbm_surface_destroy() when no longer needed. If an error occurs
 416  * during allocation %NULL will be returned.
 417  *
 418  * \sa enum gbm_bo_format for the list of formats
 419  */
 420 GBM_EXPORT struct gbm_surface *
 421 gbm_surface_create(struct gbm_device *gbm,
 422                    uint32_t width, uint32_t height,
 423                    uint32_t format, uint32_t flags)
 424 {
 425    return gbm->surface_create(gbm, width, height, format, flags);
 426 }
 427
 428 /**
 429  * Destroys the given surface and frees all resources associated with
 430  * it.
 431  *
 432  * All buffers locked with gbm_surface_lock_front_buffer() should be
 433  * released prior to calling this function.
 434  *
 435  * \param surf The surface
 436  */
 437 GBM_EXPORT void
 438 gbm_surface_destroy(struct gbm_surface *surf)
 439 {
 440    surf->gbm->surface_destroy(surf);
 441 }
 442
 443 /**
 444  * Lock the surface's current front buffer
 445  *
 446  * Lock rendering to the surface's current front buffer until it is
 447  * released with gbm_surface_release_buffer().
 448  *
 449  * This function must be called exactly once after calling
 450  * eglSwapBuffers.  Calling it before any eglSwapBuffer has happened
 451  * on the surface or two or more times after eglSwapBuffers is an
 452  * error.  A new bo representing the new front buffer is returned.  On
 453  * multiple invocations, all the returned bos must be released in
 454  * order to release the actual surface buffer.
 455  *
 456  * \param surf The surface
 457  *
 458  * \return A buffer object that should be released with
 459  * gbm_surface_release_buffer() when no longer needed.  The implementation
 460  * is free to reuse buffers released with gbm_surface_release_buffer() so
 461  * this bo should not be destroyed using gbm_bo_destroy().  If an error
 462  * occurs this function returns %NULL.
 463  */
 464 GBM_EXPORT struct gbm_bo *
 465 gbm_surface_lock_front_buffer(struct gbm_surface *surf)
 466 {
 467    return surf->gbm->surface_lock_front_buffer(surf);
 468 }
 469
 470 /**
 471  * Release a locked buffer obtained with gbm_surface_lock_front_buffer()
 472  *
 473  * Returns the underlying buffer to the gbm surface.  Releasing a bo
 474  * will typically make gbm_surface_has_free_buffer() return 1 and thus
 475  * allow rendering the next frame, but not always. The implementation
 476  * may choose to destroy the bo immediately or reuse it, in which case
 477  * the user data associated with it is unchanged.
 478  *
 479  * \param surf The surface
 480  * \param bo The buffer object
 481  */
 482 GBM_EXPORT void
 483 gbm_surface_release_buffer(struct gbm_surface *surf, struct gbm_bo *bo)
 484 {
 485    surf->gbm->surface_release_buffer(surf, bo);
 486 }
 487
 488 /**
 489  * Return whether or not a surface has free (non-locked) buffers
 490  *
 491  * Before starting a new frame, the surface must have a buffer
 492  * available for rendering.  Initially, a gbm surface will have a free
 493  * buffer, but after one or more buffers have been locked (\sa
 494  * gbm_surface_lock_front_buffer()), the application must check for a
 495  * free buffer before rendering.
 496  *
 497  * If a surface doesn't have a free buffer, the application must
 498  * return a buffer to the surface using gbm_surface_release_buffer()
 499  * and after that, the application can query for free buffers again.
 500  *
 501  * \param surf The surface
 502  * \return 1 if the surface has free buffers, 0 otherwise
 503  */
 504 GBM_EXPORT int
 505 gbm_surface_has_free_buffers(struct gbm_surface *surf)
 506 {
 507    return surf->gbm->surface_has_free_buffers(surf);
 508 }